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dc.contributor.authorJorstad, Svetlana G.en_US
dc.contributor.authorMarscher, Alan P.en_US
dc.contributor.authorMorozova, Daria A.en_US
dc.contributor.authorTroitsky, Ivan S.en_US
dc.contributor.authorAgudo, Ivanen_US
dc.contributor.authorCasadio, Carolinaen_US
dc.contributor.authorFoord, Adien_US
dc.contributor.authorGomez, Jose L.en_US
dc.contributor.authorMacDonald, Nicholas R.en_US
dc.contributor.authorMolina, Sol N.en_US
dc.contributor.authorLahteenmaki, Anneen_US
dc.contributor.authorTammi, Jonien_US
dc.contributor.authorTornikoski, Merjaen_US
dc.date.accessioned2017-12-06T15:52:47Z
dc.date.available2017-12-06T15:52:47Z
dc.date.issued2017-09-10
dc.identifierhttp://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000413735300001&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=6e74115fe3da270499c3d65c9b17d654
dc.identifier.citationSvetlana G Jorstad, Alan P Marscher, Daria A Morozova, Ivan S Troitsky, Ivan Agudo, Carolina Casadio, Adi Foord, Jose L Gomez, Nicholas R MacDonald, Sol N Molina, Anne Lahteenmaki, Joni Tammi, Merja Tornikoski. 2017. "Kinematics of Parsec-scale Jets of Gamma-Ray Blazars at 43GHz within the VLBA-BU-BLAZAR Program." Astrophysical Journal, v. 846, issue 2, pp. (35).
dc.identifier.issn0004-637X
dc.identifier.issn1538-4357
dc.identifier.urihttps://hdl.handle.net/2144/25751
dc.description.abstractWe analyze the parsec-scale jet kinematics from 2007 June to 2013 January of a sample of γ-ray bright blazars monitored roughly monthly with the Very Long Baseline Array at 43 GHz. In a total of 1929 images, we measure apparent speeds of 252 emission knots in 21 quasars, 12 BL Lacertae objects (BLLacs), and 3 radio galaxies, ranging from 0.02c to 78c; 21% of the knots are quasi-stationary. Approximately one-third of the moving knots execute non-ballistic motions, with the quasars exhibiting acceleration along the jet within 5 pc (projected) of the core, and knots in BLLacs tending to decelerate near the core. Using the apparent speeds of the components and the timescales of variability from their light curves, we derive the physical parameters of 120 superluminal knots, including variability Doppler factors, Lorentz factors, and viewing angles. We estimate the half-opening angle of each jet based on the projected opening angle and scatter of intrinsic viewing angles of knots. We determine characteristic values of the physical parameters for each jet and active galactic nucleus class based on the range of values obtained for individual features. We calculate the intrinsic brightness temperatures of the cores, T core, at all b, int epochs, finding that the radio galaxies usually maintain equipartition conditions in the cores, while ∼30% of T core b, int measurements in the quasars and BLLacs deviate from equipartition values by a factor >10. This probably occurs during transient events connected with active states. In the Appendix, we briefly describe the behavior of each blazar during the period analyzed.en_US
dc.description.sponsorshipWe thank the referee for constructive comments, which helped to improve the paper. We thank J. Romney and R. C. Walker for valuable advice regarding the receiver setup for our observations. The research at Boston University was supported by NASA through a number of Fermi Guest Investigator program grants, most recently NNX14AQ58G. The St. Petersburg University group acknowledges support from the Russian Science Foundation grant 17-12-01029. The research at the IAA-CSIC was supported in part by MINECO through grant AYA2016-80889-P, and several previous ones. I. A. acknowledges support by a Ramon y Cajal grant of the Ministerio de Economia y Competitividad (MINECO) of Spain. The VLBA is an instrument of the Long Baseline Observatory. The Long Baseline Observatory is a facility of the National Science Foundation operated by Associated Universities, Inc. (NNX14AQ58G - NASA through a number of Fermi Guest Investigator program grants; 17-12-01029 - Russian Science Foundation; AYA2016-80889-P - MINECO; Ramon y Cajal grant of the Ministerio de Economia y Competitividad (MINECO) of Spain)en_US
dc.format.extentp. 1-35en_US
dc.languageEnglish
dc.publisherInstitute of Physics Publishing Ltden_US
dc.relation.ispartofAstrophysical Journal
dc.rights© 2017. The American Astronomical Society. All rights reserved.en_US
dc.subjectScience & technologyen_US
dc.subjectPhysical sciencesen_US
dc.subjectAstronomy & astrophysicsen_US
dc.subjectGalaxies: activeen_US
dc.subjectGalaxies: jetsen_US
dc.subjectTechniques: interferometricen_US
dc.subjectActive galactic nucleien_US
dc.subjectLarge-area telescopeen_US
dc.subjectBL Lacertae objectsen_US
dc.subjectBase-line arrayen_US
dc.subjectEgret-detected quasarsen_US
dc.subjectGalaxy 3C 120en_US
dc.subjectMultiwavelength observationsen_US
dc.subjectRelativistic jetsen_US
dc.subjectPKS 1510-089en_US
dc.subjectX-rayen_US
dc.titleKinematics of Parsec-scale jets of Gamma-ray blazars at 43GHz within the VLBA-BU-BLAZAR programen_US
dc.typeArticleen_US
dc.identifier.doi10.3847/1538-4357/aa8407
pubs.elements-sourceweb-of-scienceen_US
pubs.notesEmbargo: Not knownen_US
pubs.organisational-groupBoston Universityen_US
pubs.organisational-groupBoston University, College of Arts & Sciencesen_US
pubs.organisational-groupBoston University, College of Arts & Sciences, Department of Astronomyen_US
pubs.publication-statusPublisheden_US
dc.date.online2017-09-05
dc.date.online2017-09-05
dc.identifier.orcid0000-0001-7396-3332 (Marscher, Alan P)


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